Salahuddin Bidita, Aziz Shazed, Gao Shuai, Hossain Md Shahriar A, Billah Motasim, Zhu Zhonghua, Amiralian Nasim
Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland, Brisbane, QLD 4072, Australia.
School of Chemical Engineering, The University of Queensland, Brisbane, QLD 4072, Australia.
Polymers (Basel). 2022 Nov 22;14(23):5074. doi: 10.3390/polym14235074.
Nanocomposite hydrogels are highly porous colloidal structures with a high adsorption capacity, making them promising materials for wastewater treatment. In particular, magnetic nanoparticle (MNP) incorporated hydrogels are an excellent adsorbent for aquatic pollutants. An added advantage is that, with the application of an external magnetic field, magnetic hydrogels can be collected back from the wastewater system. However, magnetic hydrogels are quite brittle and structurally unstable under compact conditions such as in fixed-bed adsorption columns. To address this issue, this study demonstrates a unique hydrogel composite bead structure, providing a good adsorption capacity and superior compressive stress tolerance due to the presence of hollow cores within the beads. The gel beads contain alginate polymer as the matrix and MNP-decorated cellulose nanofibres (CNF) as the reinforcing agent. The MNPs within the gel provide active adsorption functionality, while CNF provide a good stress transfer phenomenon when the beads are under compressive stress. Their adsorption performance is evaluated in a red mud solution for pollutant adsorption. Composite gel beads have shown high performance in adsorbing metal (aluminium, potassium, selenium, sodium, and vanadium) and non-metal (sulphur) contaminations. This novel hybrid hydrogel could be a promising alternative to the conventionally used toxic adsorbent, providing environmentally friendly operational benefits.
纳米复合水凝胶是具有高吸附容量的高度多孔胶体结构，使其成为废水处理的有前景的材料。特别是，掺入磁性纳米颗粒（MNP）的水凝胶是一种用于去除水中污染物的优良吸附剂。另一个优点是，在施加外部磁场时，磁性水凝胶可以从废水系统中回收。然而，磁性水凝胶在紧凑条件下（如在固定床吸附柱中）相当脆且结构不稳定。为了解决这个问题，本研究展示了一种独特的水凝胶复合珠结构，由于珠内存在中空核，具有良好的吸附容量和优异的抗压应力耐受性。凝胶珠包含藻酸盐聚合物作为基质和MNP修饰的纤维素纳米纤维（CNF）作为增强剂。凝胶中的MNP提供了活性吸附功能，而CNF在珠子受到压缩应力时提供了良好的应力传递现象。在赤泥溶液中评估了它们对污染物吸附的性能。复合凝胶珠在吸附金属（铝、钾、硒、钠和钒）和非金属（硫）污染物方面表现出高性能。这种新型杂化水凝胶可能是传统使用的有毒吸附剂的一种有前景的替代品，具有环境友好的操作优势。
